Conventionally, there has widely been known operational procedure (endoscopic operation) that carries out the operation through inserting a surgical instrument, such as an endoscope or electric scalpel, into a body cavity of a patient. When performing the operation procedure, organs other than the organ to be operated on and a greater omentum (which are hereinafter referred to “surgical obstruction”) are desirably moved to the outside of the operation field. In recent years, operations have been proposed to be performed under an endoscopic view by filling a body cavity with a liquid, such as a normal saline solution (so-called “underwater operation”, see, e.g., Non-Patent Documents 1 and 2). Under such an operational procedure, a surgical obstruction floats in the liquid and is thereby more likely to invade an operation field or area during the operation. Therefore, a device is required to prevent surgical obstructions from invading the operation field during the operation.
Patent Document 1 discloses an operation field-securing device as a device that prevents surgical obstructions from invading the operation field. The operation field-securing device includes a main body that has a plurality of wire rods arranged at intervals to form a truncated cone shape. The main body is designed to vary its maximum diameter by changing at least one of the posture and shape of the wire rods.
Patent Document 2 discloses a self-expanding deployment aid (retractor) for deployment of a field of view to clearly show the internal structure of the heart, such as that of a valve, during the operation of the heart. The retractor is configured from a cylindrical portion formed by spirally winding a soft pipe-shaped member. When operating on the heart, the retractor is placed within the heart to form a space in the heart, hence making it possible to secure a favorable field of view.
Patent Document 3 discloses an operation field-securing member that includes a pouch expandable by introducing a fluid thereinto and formed as an annular member when being expanded. The operation field-securing member is designed to secure an operation field inside the annular member, within a body cavity. The annular member is partially provided with penetration parts that communicate between the inside and outside of the annular member.
Patent Document 4 discloses a water tank for use in the underwater operation. The water tank includes a water-tank main body set in contact with a body wall and in which a liquid supplied into the body cavity is stored, and a through-hole formed at the bottom of the water-tank main body, the through-hole causing the liquid stored in the water-tank main body to flow into the body cavity via an incision made in the body wall. The water tank further includes a coupling member that liquid-tightly couples the water-tank main body with at least one area of the body wall and a retractor attached to the incision.